Abstract

Powder coating is an important process for many different industries. It focuses on modifying the surface properties and/or functionality of powders that the natural product does not offer. Surface modification of particles can be done by wet and dry coating methods. However, wet coating methods have become less desirable recently because of environmental concerns over the resulting waste streams and possible VOC emissions. Dry powder coating is an alternative technology avoiding the previous drawbacks, and with the advantages of having small processing time, of being environmentally friendly and with relatively low energy costs. Dry particle coating consists of three main terms: powder couple, process and the end-use properties of the composite particles. The objective of this study is the have a fundamental knowledge on dry particle coating to better understand the interactions between these terms and also classify the criteria that affect the end-use properties of the particles. In this work, two different model couples have been treated by different equipments and the end-use properties of the composite particles have been compared with each other by using several characterization techniques. In the first part of the study, we focus on the processes and their operating conditions influencing the coating phenomena and to the development of the AFM technique to derive coating coverage information. In the second part the influence of the size of the host and guest particles on the end-use properties are studied